HttpClient不会在Android Studio中导入

Question

我有一个用Android Studio编写的简单类：

package com.mysite.myapp;

import org.apache.http.client.HttpClient;

public class Whatever {
    public void headBangingAgainstTheWallExample () {
        HttpClient client = new DefaultHttpClient();
    }
}

从这里我得到以下编译时错误：

Cannot resolve symbol HttpClient

Android Studio SDK中不包含HttpClient吗？即使不是，我也将它添加到我的Gradle构建中：

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:23.0.0'
    compile 'org.apache.httpcomponents:httpclient:4.5'
}

无论有没有最后一个编译行，错误都是一样的。我错过了什么？

Answer 1

在sdk 23中不再支持HttpClient。你必须使用URLConnection或降级到sdk 22（compile 'com.android.support:appcompat-v7:22.2.0'）

如果您需要sdk 23，请将其添加到您的gradle中：

android {
    useLibrary 'org.apache.http.legacy'
}

您也可以尝试下载并将HttpClient jar直接包含在您的项目中，或使用OkHttp代替

Answer 2

Android 6.0（API Level 23）版本删除了对Apache HTTP客户端的支持。因此，您不能直接在API 23中使用此库。但有一种方法可以使用它。在build.gradle文件中添加useLibrary'org.apache.http.legacy'，如下所示 -

android {
    useLibrary 'org.apache.http.legacy'
}

如果这不起作用，您可以应用以下hack-

- 将/ SDK / android-23 / Android SDK目录的可选路径中的org.apache.http.legacy.jar复制到项目的app / libs文件夹中。

- 现在在build.gradle文件的dependencies {}部分中添加编译文件（'libs / org.apache.http.legacy.jar'）。

Answer 3

如果你想导入一些类，如：

import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient; 
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;

您可以在build.gradle中添加以下行（Gradle依赖项）

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:27.1.0'
    implementation 'com.android.support:support-v4:27.1.0'

    .
    .
    .

    implementation 'org.jbundle.util.osgi.wrapped:org.jbundle.util.osgi.wrapped.org.apache.http.client:4.1.2'

}

Answer 4

在v23 sdk中删除了ApacheHttp客户端。您可以使用HttpURLConnection或第三方Http Client，如OkHttp。

ref：https://developer.android.com/preview/behavior-changes.html#behavior-apache-http-client

Answer 5

只需使用： -

android {
         .
         .
         .
 useLibrary 'org.apache.http.legacy'
         .
         .
         .
          }

Answer 6

sdk 23和23+不支持HttpClient。

如果您需要使用sdk 23，请将以下代码添加到您的gradle中：

android {
    useLibrary 'org.apache.http.legacy'
}

它为我工作。希望对你有用。

Answer 7

如果您需要sdk 23，请将其添加到您的gradle中：

android {
    useLibrary 'org.apache.http.legacy'
}

Answer 8

你只需要添加一行

useLibrary 'org.apache.http.legacy'

例如，到build.gradle（Module：app）

apply plugin: 'com.android.application'

android {
    compileSdkVersion 24
    buildToolsVersion "25.0.0"

    useLibrary 'org.apache.http.legacy'

    defaultConfig {
        applicationId "com.avenues.lib.testotpappnew"
        minSdkVersion 15
        targetSdkVersion 24
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    compile 'com.android.support:appcompat-v7:24.2.1'
    testCompile 'junit:junit:4.12'
}

Answer 9

您的项目中有哪个API目标？AndroidHttpClientis仅适用于API级别8 here

享受你的代码:)

Answer 10

如前所述，org.apache.http.client.HttpClient不再受支持：

SDK（API级别）＃23。

你必须使用java.net.HttpURLConnection。

如果你想在使用HttpURLConnection时让你的代码（和生命）更容易，这里有一个Wrapper这个类，它可以让你使用GET对POST，PUT和JSON进行简单的操作，比如做一个HTTP PUT。

HttpRequest request = new HttpRequest(API_URL + PATH).addHeader("Content-Type", "application/json");
int httpCode = request.put(new JSONObject().toString());
if (HttpURLConnection.HTTP_OK == httpCode) {
    response = request.getJSONObjectResponse();
} else {
  // log error
}
httpRequest.close()

随意使用它。

package com.calculistik.repository;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

/**
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 * <p>
 * Copyright © 2017, Calculistik . All rights reserved.
 * <p>
 * Oracle and Java are registered trademarks of Oracle and/or its
 * affiliates. Other names may be trademarks of their respective owners.
 * <p>
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common
 * Development and Distribution License("CDDL") (collectively, the
 * "License"). You may not use this file except in compliance with the
 * License. You can obtain a copy of the License at
 * https://netbeans.org/cddl-gplv2.html or
 * nbbuild/licenses/CDDL-GPL-2-CP. See the License for the specific
 * language governing permissions and limitations under the License.
 * When distributing the software, include this License Header
 * Notice in each file and include the License file at
 * nbbuild/licenses/CDDL-GPL-2-CP. Oracle designates this particular file
 * as subject to the "Classpath" exception as provided by Oracle in the
 * GPL Version 2 section of the License file that accompanied this code. If
 * applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
 * "Portions Copyrighted [year] [name of copyright owner]"
 * <p>
 * Contributor(s):
 * Created by alejandro tkachuk @aletkachuk
 * www.calculistik.com
 */
public class HttpRequest {

    public static enum Method {
        POST, PUT, DELETE, GET;
    }

    private URL url;
    private HttpURLConnection connection;
    private OutputStream outputStream;
    private HashMap<String, String> params = new HashMap<String, String>();

    public HttpRequest(String url) throws IOException {
        this.url = new URL(url);
        connection = (HttpURLConnection) this.url.openConnection();
    }

    public int get() throws IOException {
        return this.send();
    }

    public int post(String data) throws IOException {
        connection.setDoInput(true);
        connection.setRequestMethod(Method.POST.toString());
        connection.setDoOutput(true);
        outputStream = connection.getOutputStream();
        this.sendData(data);
        return this.send();
    }

    public int post() throws IOException {
        connection.setDoInput(true);
        connection.setRequestMethod(Method.POST.toString());
        connection.setDoOutput(true);
        outputStream = connection.getOutputStream();
        return this.send();
    }

    public int put(String data) throws IOException {
        connection.setDoInput(true);
        connection.setRequestMethod(Method.PUT.toString());
        connection.setDoOutput(true);
        outputStream = connection.getOutputStream();
        this.sendData(data);
        return this.send();
    }

    public int put() throws IOException {
        connection.setDoInput(true);
        connection.setRequestMethod(Method.PUT.toString());
        connection.setDoOutput(true);
        outputStream = connection.getOutputStream();
        return this.send();
    }

    public HttpRequest addHeader(String key, String value) {
        connection.setRequestProperty(key, value);
        return this;
    }

    public HttpRequest addParameter(String key, String value) {
        this.params.put(key, value);
        return this;
    }

    public JSONObject getJSONObjectResponse() throws JSONException, IOException {
        return new JSONObject(getStringResponse());
    }

    public JSONArray getJSONArrayResponse() throws JSONException, IOException {
        return new JSONArray(getStringResponse());
    }

    public String getStringResponse() throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream()));
        StringBuilder response = new StringBuilder();
        for (String line; (line = br.readLine()) != null; ) response.append(line + "\n");
        return response.toString();
    }

    public byte[] getBytesResponse() throws IOException {
        byte[] buffer = new byte[8192];
        InputStream is = connection.getInputStream();
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        for (int bytesRead; (bytesRead = is.read(buffer)) >= 0; )
            output.write(buffer, 0, bytesRead);
        return output.toByteArray();
    }

    public void close() {
        if (null != connection)
            connection.disconnect();
    }

    private int send() throws IOException {
        int httpStatusCode = HttpURLConnection.HTTP_BAD_REQUEST;

        if (!this.params.isEmpty()) {
            this.sendData();
        }
        httpStatusCode = connection.getResponseCode();

        return httpStatusCode;
    }

    private void sendData() throws IOException {
        StringBuilder result = new StringBuilder();
        for (Map.Entry<String, String> entry : params.entrySet()) {
            result.append((result.length() > 0 ? "&" : "") + entry.getKey() + "=" + entry.getValue());//appends: key=value (for first param) OR &key=value(second and more)
        }
        sendData(result.toString());
    }

    private HttpRequest sendData(String query) throws IOException {
        BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
        writer.write(query);
        writer.close();
        return this;
    }

}

Answer 11

在依赖项下添加这两行

compile 'org.apache.httpcomponents:httpcore:4.4.1'
compile 'org.apache.httpcomponents:httpclient:4.5'

然后

useLibrary 'org.apache.http.legacy'

在android下

Answer 12

HttpClient在API级别22中已弃用，在API级别23中已删除。如果必须，您仍可在API级别23及更高版本中使用它，但最好转移到支持的方法来处理HTTP。因此，如果您使用23进行编译，请在build.gradle中添加：

android {
    useLibrary 'org.apache.http.legacy'
}

Answer 13

另一种方法是如果你有httpclient.jar文件，那么你可以这样做：

将.jar文件粘贴到项目的“libs文件夹”中。然后在gradle中在build.gradle中添加这一行（Module：app）

dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
compile 'com.android.support:appcompat-v7:23.0.0'
compile files('libs/httpcore-4.3.3.jar')
}

Answer 14

错误：（30,0）未找到Gradle DSL方法：'classpath（）'可能的原因：

项目'cid'可能正在使用不包含该方法的Android Gradle插件版本（例如，在1.1.0中添加了'testCompile'）。将插件升级到版本2.3.3并同步项目

项目'cid'可能正在使用不包含该方法的Gradle版本。打开Gradle包装文件

构建文件可能缺少Gradle插件。应用Gradle插件

Answer 15

我认为根据你拥有的Android Studio版本，重要的是你更新你的android工作室，我也很沮丧，遵循大家的建议，但没有运气，直到我不得不将我的Android版本从1.3升级到1.5，错误消失了魔法。

Answer 16

TejaDroid在以下链接中的答案帮助了我。 Can't import org.apache.http.HttpResponse in Android Studio

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    compile 'com.android.support:appcompat-v7:23.0.1'

    compile 'org.jbundle.util.osgi.wrapped:org.jbundle.util.osgi.wrapped.org.apache.http.client:4.1.2'
    ...
}

Answer 17

要使用Apache HTTP for SDK Level 23：

顶级build.gradle - /build.gradle

buildscript {
    ...
    dependencies {
        classpath 'com.android.tools.build:gradle:1.5.0' 
        // Lowest version for useLibrary is 1.3.0
        // Android Studio will notify you about the latest stable version
        // See all versions: http://jcenter.bintray.com/com/android/tools/build/gradle/
    }
    ...
}

来自Android工作室的关于gradle更新的通知：

特定于模块的build.gradle - /app/build.gradle

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.2"
    ...
    useLibrary 'org.apache.http.legacy'
    ...
}

Answer 18

试试这个为我工作将此依赖项添加到build.gradle文件中

compile 'org.jbundle.util.osgi.wrapped:org.jbundle.util.osgi.wrapped.org.apache.http.client:4.1.2'

Answer 19

1-下载Apache jar文件（截至此答案）4.5.zip文件来自： https://hc.apache.org/downloads.cgi?Preferred=http%3A%2F%2Fapache.arvixe.com%2F

2-打开zip文件将jar文件复制到libs文件夹中。你可以找到它，如果你到项目的顶部说“Android”，当你点击它时你会找到一个列表。所以，

Android - >项目 - > app - > libs

，然后把罐子放在那里。

3-在build.gradle（Module：app）中添加

compile fileTree(dir: 'libs', include: ['*.jar'])

在

 dependency { 
   }

4-在java类中添加以下导入：

import org.apache.http.HttpResponse;

import org.apache.http.client.HttpClient;

import org.apache.http.client.methods.HttpGet;

import org.apache.http.impl.client.DefaultHttpClient;

import org.apache.http.params.CoreProtocolPNames;

Answer 20

在sdk 23中不再支持HttpClient.Android 6.0（API Level 23）版本删除了对Apache HTTP客户端的支持。你必须使用

android {
    useLibrary 'org.apache.http.legacy'
    .
    .
    .

并在您的依赖项中添加以下代码段：

//用于Web服务的http最终解决方案（包括文件上传）

compile('org.apache.httpcomponents:httpmime:4.3.6') {
        exclude module: 'httpclient'
}
 compile 'org.apache.httpcomponents:httpclient-android:4.3.5'

当您使用“使用MultipartEntity进行文件上载”时，它也会对您有所帮助。

Answer 21

在API 22中它们被弃用了，在API 23中它们完全删除了它们，如果你不需要新添加的所有花哨的东西，只需使用apache之前集成的API中的.jar文件，这是一个简单的解决方法，但是作为分隔的.jar文件：

1. http://hc.apache.org/downloads.cgi
2. download httpclient 4.5.1, the zile file
3. unzip all files
4. drag in your project httpclient-4.5.1.jar, httpcore-4.4.3.jar and httpmime-4.5.1.jar
5. project, right click, open module settings, app, dependencies, +, File dependency and add the 3 files
6. now everything should compile properly

Answer 22

您只需将其添加到Gradle依赖项：

compile "org.apache.httpcomponents:httpcore:4.3.2"